Soil erosion

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  • The book deals with several aspects of soil erosion, focusing on its connection with the agricultural world. Chapters' topics are various, ranging from irrigation practices to soil nutrient, land use changes or tillage methodologies. The book is subdivided into fourteen chapters, sorted in four sections, grouping different facets of the topic: introductive case studies, erosion management in vineyards, soil erosion issue in dry environments, and erosion control practices.

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  • Soil erosion affects a large part of the Earth surface, and it represents one of the most relevant environmental problems worldwide. Intense land degradation processes that destroyed civilizations in the past are still going on at present. Accelerated soil erosion is one of the main soil threats, as the natural balance between soil formation and loss may be seriously compromised, leading to desertification and permanent loss of fertility and protective function. Soil erosion is not only related to agricultural activities and farming practices, but also to land management in general....

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  • Soil erosion is a hazard traditionally associated with agriculture in tropical and semi-arid areas and is important for its long-term effects on soil productivity and sustainable agriculture. It is, however, a problem of wider significance occurring additionally on land devoted to forestry, transport and recreation. Erosion also leads to environmental damage through sedimentation, pollution and increased flooding. The costs associated with the movement and deposition of sediment in the landscape frequently outweigh those arising from the long-term loss of soil in eroding fields.

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  • Soil loss for erosion is a natural phenomenon in soil dynamics, influenced by climate, soil intrinsic properties, and morphology, that can both trigger and enhance the process. Anthropic activities, like inappropriate agricultural practices, deforestation, overgrazing, forest fires and construction activities, may exert a remarkable impact on erosion processes or, on the other hand, contribute to soil erosion mitigation through a sustainable management of natural resources.

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  • The papers in this book provide new information on several aspects of soil erosion and applications of the National Resources Inventory (NRI). They were commissioned following a planning workshop in July 1984 and were presented in December 1984 during a national convocation, “Physical Dimensions of the Erosion Problem.” The workshop and convocation were held by the National Research Council's Board on Agriculture in response to a request from the Soil Conservation Service of the U.S.

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  • “Essentially, all life depends upon the soil. There can be no life without soil and no soil without life; they have evolved together.” - Charles E. Kellogg, USDA Yearbook of Agricul‐ ture, 1938. Natural processes and human activities alter the properties and quality of soils over time. The assessment of soil quality entails the evaluation of the capability of a soil to perform its functions not only in present scenarios but also how those functions can be preserved for future land...

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  • Soils are aggregates of mineral particles, and together with air and/or water in the void spaces, they form three-phase systems. A large portion of the earth’s surface is covered by soils, and they are widely used as construction and foundation materials. Soil mechanics is the branch of engineering that deals with the engineering properties of soils and their behavior under stress.

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  • This book on conservation and improvement of the forest soil is intended for students at agricultural universities who specialise in soil improvement and for all readers who are interested in conservation of the forest environment. The development of human society largely depends on the exploitation of the biosphere. Unfortunately, its resources cannot last forever: some may diminish, others may be irreversibly damaged or destroyed.

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  • Forests play an important role in reducing erosion. In Vietnam, destroying natural forests in mountainous areas has caused serious environmental problems for sustainable development. Required forest areas for protection of soils from erosion in Vietnam are defined in this study. An algorithm of defining required forest area for soil erosion prevention is based on a comparison of soil loss prediction and its threshold of 10 ton ha-1yr-1 (soil loss tolerance) within the GIS environment. Soil loss is predicted from rainfall erosivity index, slope, porosity and...

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  • First, recall that the SNIFF emissions inventory discussed above clearly indicates that industry is not the leading source of particulate emissions in Ciudad Juárez. Rather, the leading sources are vehicles, unpaved roads, and soil erosion (Table 1). Moreover, even leaving aside vehicles and soils, the single most important industrial subsector in terms of air pollution is brick kilns, not maquiladoras (Table 2). In fact, brick kilns emit more particulate matter than all other industrial plants combined.

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  • ần lớn, tới 95% bô ­ xít trên thế giới khai thác lộ thiên. Trong ngành mỏ, đây là phương thức khai thác đòi hỏi chiếm dụng nhiều đất, có tác hại huỷ diệt hệ thực vật và động vật (flora & fauna), làm xói mòn trôi lấp đất (soil erosion).

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  • Nghiên cứu khoa học: Ứng dụng Gis & phương trình Usle tính toán xói mòn đất cho một khu vực (Lưu vực, Tỉnh) với mục tiêu ứng dụng phương trình xói mòn Usle trong việc dự báo xói mòn trong một lưu vực, ước lượng off-site soil erosion sử dụng khái niệm SDR, ứng dụng Spreadsheet và kỹ thuật GIS để vẽ lên bản đồ xói mòn đất.

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  • 1) Ứng dụng GIS tính tóan R- factor (nhân tố lượng mưa) trong phương trình xói mòn USLE (Universal Soil Loss Equation) trong việc dự báo xói mòn trong một lưu vực; (on-site soil erosion); 2) Ứng dụng GIS tính tóan LS-factor (độ dốc) trong phương trình xói mòn USLE (Universal Soil Loss Equation); 3) Ứng dụng GIS tính tóan K –factor (độ xói mòn của đất), CP-factor (nhân tố che phủ của tham thực vật và hình thức canh tác)...

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  • Despite the tremendous progress that has been achieved in water pollution, almost 40% of the U.S. waters that have been assessed by states do not meet water quality goals. About 20,000 water bodies are impacted by siltation, nutrients, bacteria, oxygen depletion substances, metals, habitat alterations, pesticides, and toxic organic chemicals. With pollution from point sources being dramatically reduced, nonpoint source pollution is the major cause of most water that does not meet water quality goals.

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  • 6 Using cropping systems to control erosion Rotation and fallow Many tropical farming systems have originated from shifting cultivation; a system of food production based on a rotation of cultivation followed by a long fallow period. The fallow period ensures a natural recovery of soil fertility.

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  • 3 Soil Bioengineering The transformation of watersheds is a characteristic of human civilization. Humans transform natural landscapes into various kinds of “land use” that provide them with habitation and resources. Altered hydrology and soil erosion occur as a consequence of these transformations.

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  • Some twenty five countries have experimented with environmental accounting over the past twenty years. A few European countries have established physical accounting systems which are routinely compiled and applied to economic and environmental policy-making. Many other countries have undertaken more limited or one-time experiments and case studies with monetary environmental accounts, focused on issues such as forestry, soil erosion, and minerals depletion. A few examples suggest the richness of their experience.

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  • This book is a compilation of 29 chapters focused on: pesticides and food production, environmental effects of pesticides, and pesticides mobility, transport and fate. The first book section addresses the benefits of the pest control for crop protection and food supply increasing, and the associated risks of food contamination.

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  • The management of the Australian landscape has occupied a central position in Australian politics since the re-settlement of this continent over 200 years ago. Environmental manage- ment, long recognised as technically complex and challenging, has also been contentious and controversial. The issues associated with coping with lingering droughts, the prospects of sig- nificant climate change, and stemming soil erosion on agricultural lands are now of broad, popular interest.

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  • Grasslands occur on every continent except Antarctica, and constitute about 34 percent of the global terrestrial carbon stock. Changes in grassland vegetation due to overgrazing, conversion to crop land, desertification, fire, fragmentation, and introduction of non‐native species affect their carbon storage capacity, and may in some cases even lead to grasslands becoming a net source of CO2. For example, they may lose 20 to 50 percent of their soil organic carbon content through cultivation, soil erosion, and land degradation.

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